This invention relates to the dispensing of attachment members and, more particularly, to the dispensing of attachment members from continuously connected fastener stock.
Techniques for dispensing attachment members from continuously connected fastener stock are disclosed in U.S. Pat. No. 4,121,487, issued Oct. 24, 1978; U.S. Pat. No. 4,039,078, issued Aug. 2, 1977 and U.S. Pat. No. 3,948,128 issued Apr. 6, 1976. In these patents fastener attachment stock is formed by continuously connected plastic side members that are intercoupled by a plurality of cross links. The stock may be produced from flexible plastic materials, such as nylon, polyethylene and polypropylene, by molding or stamping.
Such attachment members can be dispensed to couple buttons to fabric, merchandising tags to articles of commerce, and in the general attachment of one item to another, such as the attachment of tubing to a chasses or electrical wiring to a frame.
In U.S. Pat. Nos. 4,121,487; 4,039,078; and 3,948,128 the stock is severed by relatively movable die members to form individual fastener attachments that are dispensed through one or more hollow slotted needles after appropriate positioning. The dispensing mechanism is provided by an ejector which forces an end bar portion of an individual fastener through the bore of a hollow needle during a forward stroke. During the return stroke of the ejector a further individual fastener is moved into position for being dispensed. If the ejector is operated prematurely, before it has completed its return stroke, it can interfere with the positioning and dispensing of the successive fastener.
Another technique for the dispensing of continuously connected fastener stock is disclosed in copending application Ser. No. 827,276, filed Aug. 24, 1977. Here the end bars of the stock, which are dispensed through the bore of a slotted hollow needle, are separated one from the other either during alignment of the end bar with the bore or during the subsequent impact of the ejector with the end bar in the course of driving it through the bore. Any remaining connection of successive fasteners is severed, for example, in the manner illustrated in U.S. Pat. No. 3,733,657. Here again the ejector dispenses an individual fastener during its forward stroke and a successive fastener is positioned for being dispensed during the return stroke. If the ejector is operated prematurely before it has completed its return stroke, it can interfere with the positioning of the successive fasteners as well as with the action of the ejector on those fasteners.
Accordingly it is an object of the invention to facilitate the dispensing of fasteners. A related objective is to facilitate the dispensing of fasteners from connected stock, particularly continuously connected stock.
Another object of the invention is to curtail the occurrence of malfunctions in the dispensing of fasteners. A related object is to curtail the occurrence of malfunctions in the dispensing of fasteners from connected stock, particularly continuously connected stock.
A further object of the invention is to assure completion of the return stroke of the ejector used in the dispensing of fasteners. A related object is to assure the completion of the return stroke of the ejector in the dispensing of fasteners from connected stock, particularly continuously connected stock.
Still another object is to curtail the occurrence of possible premature operation in the dispensing of fasteners, particularly from continuously connected stock.
Representative prior art dealing with individual fasteners is to be found in the following U.S. Pat. Nos. 3,103,666; 3,470,834; 3,494,004; 3,185,367; 3,650,451, 3,650,452; 3,652,004; 3,734,375 and 3,299,483.